Disease relevance of Ventricular Fibrillation

• At a mean follow-up time of 12.7 +/- 8.8 months (range, three to 36), amiodarone was successful in nine of 16 patients with recurrent ventricular fibrillation and 21 of 29 with recurrent ventricular tachycardia [1].
• Three missense mutations associated with long QT syndrome and ventricular fibrillation are identified in the gene for MiRP1 [2].
• Clinical studies have shown parenteral bretylium to be effective in suppressing ventricular arrhythmias, particularly recurrent, drug resistant ventricular tachycardia or ventricular fibrillation [3].
• CONCLUSIONS: The results indicate that an increasing cumulative dose of epinephrine administered during resuscitation is independently associated with unfavorable neurologic outcome after ventricular fibrillation cardiac arrest [4].
• Bretylium increases ventricular fibrillation threshold and prevents the decrease in ventricular fibrillation threshold associated with myocardial ischemia [3].

Psychiatry related information on Ventricular Fibrillation

• In this model, the incidence of ventricular fibrillation can be reduced by psychologic adaptation of the animal to his environment, cryoblockade of frontal cortical brain stem pathways and by central administration of propranolol [5].
• During cardiac catheterization and twice 24 hours later she developed ventricular fibrillation treated with electroshock and prevented later with propranolol [6].

High impact information on Ventricular Fibrillation

• We measured the rates of total and cardiac norepinephrine spillover into the plasma, which reflect respectively overall and cardiac sympathetic nervous activity, in 12 patients who had recovered from a spontaneous, sustained episode of ventricular tachycardia or ventricular fibrillation outside the hospital 4 to 48 days earlier [7].
• However, there were 17 cases of ventricular fibrillation in the placebo group (697 patients) and only 6 in the metoprolol group (698 patients, P less than 0.05) [8].
• We evaluated the effects of amiodarone in 45 patients with recurrent ventricular tachycardia or ventricular fibrillation [1].
• Tyrosine administration decreases vulnerability to ventricular fibrillation in the normal canine heart [9].
• DESIGN--Placebo-controlled, randomized, double-blind trial of nimodipine compared with placebo in out-of-hospital ventricular fibrillation [10].

Chemical compound and disease context of Ventricular Fibrillation

• Lidocaine to prevent ventricular fibrillation: easy does it [11].
• INTERVENTIONS.--Cardiac arrest was induced by ventricular fibrillation in mechanically ventilated pigs anesthetized with pentobarbital sodium [12].
• A hypertonic solution of sodium bicarbonate, Carbicarb (an equimolar mixture of sodium bicarbonate and sodium carbonate [International Medication Systems, Ltd]), or sodium chloride or an isotonic solution of sodium chloride was infused into the right atrium over a 1-minute interval starting at the sixth minute of ventricular fibrillation [12].
• This prospective study evaluated the effect of coffee (275 mg of caffeine) on this substrate with programmed ventricular stimulation in 22 patients with a history of symptomatic nonsustained ventricular tachycardia, ventricular tachycardia, or ventricular fibrillation [13].
• Prophylaxis of early ventricular fibrillation by inhibition of acylcarnitine accumulation [14].

Biological context of Ventricular Fibrillation

• The incidence of ventricular fibrillation after after circumflex occlusion was reduced from 53% to 6% (p less than .01) by the infusion of prostacyclin in doses that do not alter cardiac output or peripheral resistance [15].
• Verapamil and tiapamil in prevention of ventricular fibrillation in pigs with coronary ligation. Comparative effects on left ventricular function [16].
• Preservation of ventricular function by treatment of ventricular fibrillation with phenylephrine [17].
• Cases were defined as reports of cardiac arrest, sudden death, torsade de pointes, ventricular fibrillation, and ventricular tachycardia (n = 5591), and compared with non-cases regarding the anti-HERG activity, defined as the effective therapeutic plasma concentration (ETCPunbound) divided by the HERG IC50 value, of suspected drugs [18].
• In patients with a mutation in HERG, it rendered ventricular tachycardias/ventricular fibrillation non-inducible and restored the QT interval/heart rate relationship towards a normal range [19].

Anatomical context of Ventricular Fibrillation

• Abrupt occlusion of the left anterior descending coronary artery was performed on 45 unanesthetized farm pigs in order to evaluate the relative effects on the latency to ventricular fibrillation (VFL) of 1) adaptation of the animals to the laboratory, and 2) beta-receptor blockade by propranolol [20].
• Restoration of blood supply to the ischemic myocardium provokes ventricular fibrillation in 37.5% of control dogs but in only 9% of those administered enalaprilat and 0% of captopril-treated animals [21].
• Application of Lugol's solution to the endocardium resulted in a 102 +/- 15% increase in ventricular fibrillation threshold from a control value of 26 +/- 2 to 53 +/- 6 mA (p less than .005) [22].
• Three different coupling agents, Harco pads (Hewlett-Packard), Littman pads (3M) and Redux paste (Hewlett-Packard), were assessed in 10 anesthetized dogs in which ventricular fibrillation was induced by electrical stimulation of the right ventricle [23].
• We describe a case of an 18 years old patient with a family history of hypertrophic cardiomyopathy and sudden death in whom ventricular fibrillation could be repeatedly induced by means of transesophageal atrial stimulation with 1:1 AV conduction at a rate of 200 beats min-1 and prevented by pharmacological depression of AV node [24].

Gene context of Ventricular Fibrillation

• A case of idiopathic ventricular fibrillation was found to have a novel mutation in SCN5A, in which the expressed current showed marked suppression of channel function [25].
• A decrease of IKr or IKs by mutations in either HERG, KvLQT1, or KCNE family results in inherited long QT syndrome (LQTS) with high risk for Torsades de pointes (TdP)-type polymorphic ventricular tachycardia and ventricular fibrillation [26].
• Furthermore, the high, but not low, dose of EPO administered as a single injection significantly reduced the incidence of ventricular fibrillation during reperfusion (high dose: 0%, low dose: 40.0%, control: 50.0%) [27].
• The role of heme oxygenase-related carbon monoxide and ventricular fibrillation in ischemic/reperfused hearts [28].
• Glutathione, and a combination of superoxide dismutase, catalase and mannitol also reduced the incidence of reperfusion induced ventricular fibrillation when given just before reperfusion [29].

Analytical, diagnostic and therapeutic context of Ventricular Fibrillation

• However, from 15 minutes after randomization onward, when plasma lidocaine levels were in the therapeutic range, only 2 cases of ventricular fibrillation occurred in the treated group, as compared with 12 in the control group (P less than 0.01) [30].
• Intravenous infusion of tyrosine (1, 2, or 4 milligrams per kilogram) for 20 to 30 minutes caused dose-dependent increases in the ventricular fibrillation threshold in normal dogs [9].
• METHODS AND RESULTS: After 4 minutes of ventricular fibrillation and 3 minutes of open-chest CPR, 14 pigs (24 to 26 kg) were randomized into two groups receiving either saline (n = 7) or 0.05 mg/kg angiotensin II (n = 7) [31].
• CONCLUSIONS: We conclude that administration of vasopressin leads to a significantly higher coronary perfusion pressure and myocardial blood flow than epinephrine during closed-chest CPR in a pig model of ventricular fibrillation [32].
• Tiapamil (6 mg/kg i.v.) decreased the incidence of ventricular fibrillation to 4 of 10 versus 22 of 25 in controls (p less than 0.05) and maintained left ventricular dP/dtmax after ligation (predrug value: 2,312 +/- 112 mm Hg/sec; 20 minutes after ligation: 2,139 +/- 229 mm Hg/sec) [16].

References